Complications of deep vein thrombosis in lower extremities

Complications of deep vein thrombosis in the lower limbs, what kind of disease is this? I believe many people do not know much about this disease. This is a symptom that is not common in our lives, but this disease is very harmful to our health. It mainly occurs in the elderly. People with this disease can easily cause lower limb paralysis, so we should learn more about deep vein thrombosis in the lower limbs. Let us learn about the complications of this disease.

Common symptoms of deep vein thrombosis in the lower extremities:

Pain, calf tenderness, decreased skin temperature, venous thrombosis, persistent pain, varicose veins, painful femoral swelling, inferior vena cava thrombosis, lower extremity edema

1. Symptoms:

1. Swelling of the affected limb This is the most common symptom after lower limb venous thrombosis. The tissue tension of the affected limb is high and it presents non-pitting edema. The skin color is reddish and the skin temperature is higher than that of the healthy side. When swelling is severe, blisters may appear on the skin. The location of swelling varies depending on the location of the thrombus. Patients with iliac-femoral vein thrombosis have obvious swelling of the entire affected limb; patients with calf venous plexus thrombosis have swelling only in the calf; patients with inferior vena cava thrombosis have swelling in both lower limbs. If the thrombosis starts in the iliac-femoral vein, thigh swelling will appear early. If it starts from the calf venous plexus and gradually extends to the iliac-femoral vein, the calf will swell first and then the thigh will be affected. The swelling is usually heaviest on the 2nd or 3rd day after onset and then gradually subsides. When the disease subsides, it first manifests as a decrease in tissue tension, and then a gradual reduction in the circumference of the affected limb, but it is difficult to return to normal unless the thrombus is completely removed early. In the later stage of thrombosis, although some veins have been reopened, the venous pressure in the affected limb is still high because the venous valve function has been destroyed, and its manifestations are similar to primary lower limb valvular insufficiency.

2. Pain and tenderness There are two main causes of pain:

① The blood clot causes an inflammatory reaction in the vein, causing persistent pain in the affected limb.

② The blood clot blocks the veins, obstructing the venous return of the lower limbs, causing swelling and pain in the affected limbs, and the pain worsens when standing upright.

Tenderness is mainly confined to the site of inflammatory response to venous thrombosis, such as the femoral vein or calf. Calf gastrocnemius tenderness is also called a positive Homans sign. Since squeezing the calf may cause the blood clot to dislodge, excessive force should be used during the examination.

3. Superficial varicose veins Superficial varicose veins are a compensatory reaction. When the main vein is blocked, the venous blood in the lower limbs returns through the superficial veins, causing the superficial veins to dilate compensatorily. Therefore, superficial varicose veins are generally not obvious in the acute phase and are a manifestation of the sequelae of lower limb venous thrombosis.

4. When DVT of the lower limbs extensively involves the intramuscular venous plexus, the iliofemoral veins and their side branches are completely blocked by blood clots, and tissue tension increases extremely, causing lower limb artery spasm, limb ischemia, and even necrosis. Clinically, it manifests as severe pain, shiny skin of the affected limb, accompanied by blisters or blood blisters, and the skin color is bluish-purple, which is called painful cerulea dorsi (Phlegmasia Cerulea Dolens). It is often accompanied by arterial spasm, weakened or absent arterial pulsation in the lower limbs, decreased skin temperature, and then a high degree of circulatory disorder. The patient has a strong systemic reaction, accompanied by high fever, mental weakness, and is prone to shock and wet gangrene of the lower limbs.

5. Femoral edema When acute deep vein thrombosis occurs in the lower limbs, the lower limb edema reaches its highest level within a few hours. The swelling is concave and high-tension, and the obstruction mainly occurs in the femoral venous system. When combined with infection, the stimulation causes continuous spasm of the arteries, and swelling of the entire limb, pale skin, and dilation of the subcutaneous venous network is seen, which is called painful femoral white seed (Phlegmasia Alba Dolens).

2. Complications:

The main complications of this disease are as follows:

1. Pulmonary embolism

Pulmonary embolism refers to a pathological process caused by obstruction of the pulmonary artery or its branches by emboli. The diagnosis rate is low, the misdiagnosis rate and mortality rate are high. According to literature reports, 650,000 people suffer from pulmonary embolism and 240,000 people die from it in the United States each year. According to statistics in the UK, 40,000 people suffer from non-fatal pulmonary embolism each year, and about 20,000 hospitalized patients die from pulmonary embolism. Some scholars believe that 80% to 90% of pulmonary embolism emboli originate from deep vein thrombosis in the lower extremities. Especially during thrombolytic therapy, the chance of embolus detachment is higher. Large emboli can cause death within a few minutes. It has been reported that the mortality rate of pulmonary embolism caused by iliofemoral vein thrombosis is as high as 20%~30%. Typical symptoms of pulmonary embolism are dyspnea, chest pain, cough, and hemoptysis. The three major physical signs are pulmonary rales, hyperactive second sound in the pulmonary valve area, and gallop rhythm. Therefore, prevention of pulmonary embolism is more important than treatment in clinical practice. Currently, vena cava filter placement is the most common method used in clinical practice to prevent pulmonary embolism. The inferior vena cava filter is a device made of metal wire that is placed into the inferior vena cava through a special delivery device to intercept larger blood clots in the blood flow and prevent them from entering the pulmonary artery and causing fatal pulmonary embolism. However, filter placement may cause complications such as filter displacement, blockage, and bleeding, and the cost is high, so its indications must be strictly controlled in clinical practice. 1. Complications:

2. Bleeding

The main complication of thrombolytic therapy is bleeding. Be especially alert to gastrointestinal and intracranial hemorrhage. Therefore, blood type, hemoglobin, platelets and coagulation function should be checked before thrombolytic therapy; the dosage should usually be adjusted to maintain the prothrombin time (PT) and partial prothrombin time (APTT) at 2 to 2.5 times the normal value. During and after thrombolysis, the patient should be closely observed for bleeding tendencies, such as at the vascular puncture site, skin, gums, etc. Observe for macroscopic hematuria and microscopic hematuria, abdominal pain, melena, etc. If there is bleeding at the puncture site, apply pressure to stop the bleeding. Severe bleeding should be treated with thrombolysis and blood or plasma transfusion. Patients should be instructed on self-observation and prevention of hemorrhagic complications. If there is bleeding gums, nasal bleeding, bleeding skin and mucous membranes, or black stools, advise the patient not to pick teeth, nose, or ear canals with hard or sharp objects, and do not cough hard to avoid hemoptysis; use a soft-bristled toothbrush to brush teeth, and be gentle to avoid causing unnecessary trauma; the diet should be light and easy to digest to avoid food damaging the digestive tract, and eat fiber-rich foods more often to keep bowel movements open.

3. Post-thrombotic syndrome

It is the most common and important complication. During the process of thrombus organization, the venous valves are damaged, even disappear or adhere to the vessel wall, leading to secondary deep vein valvular insufficiency, namely post-thrombotic syndrome. Post-thrombotic syndrome occurs months to years after deep vein thrombosis in the lower extremities. Its main manifestations include chronic edema, pain, muscle fatigue (venous claudication), varicose veins, pigmentation, and changes in subcutaneous tissue fibers. In severe cases, local ulcers may form, affecting the patient's quality of life. It has been reported that patients with deep vein thrombosis in the lower limbs who follow the doctor's advice, wear elastic stockings after discharge, take oral anticoagulants (such as aspirin 100 mg (/time/day)) for 3 to 6 months, avoid standing or sitting for long periods of time, and raise the affected limb when resting, generally rarely develop post-thrombotic syndrome. For patients who have developed post-thrombotic syndrome, valve repair can be used if there is valvular insufficiency. The operation should be performed gently to avoid damaging the veins. During the operation, pulse electrodes were used to stimulate the calf muscles to increase contraction and promote blood flow back. After the operation, the patient was encouraged to frequently move his feet and toes actively, and satisfactory results were achieved.